1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __LINUX_CPUMASK_H 3 #define __LINUX_CPUMASK_H 4 5 /* 6 * Cpumasks provide a bitmap suitable for representing the 7 * set of CPU's in a system, one bit position per CPU number. In general, 8 * only nr_cpu_ids (<= NR_CPUS) bits are valid. 9 */ 10 #include <linux/kernel.h> 11 #include <linux/threads.h> 12 #include <linux/bitmap.h> 13 #include <linux/atomic.h> 14 #include <linux/bug.h> 15 16 /* Don't assign or return these: may not be this big! */ 17 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; 18 19 /** 20 * cpumask_bits - get the bits in a cpumask 21 * @maskp: the struct cpumask * 22 * 23 * You should only assume nr_cpu_ids bits of this mask are valid. This is 24 * a macro so it's const-correct. 25 */ 26 #define cpumask_bits(maskp) ((maskp)->bits) 27 28 /** 29 * cpumask_pr_args - printf args to output a cpumask 30 * @maskp: cpumask to be printed 31 * 32 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask. 33 */ 34 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp) 35 36 #if NR_CPUS == 1 37 #define nr_cpu_ids 1U 38 #else 39 extern unsigned int nr_cpu_ids; 40 #endif 41 42 #ifdef CONFIG_CPUMASK_OFFSTACK 43 /* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also, 44 * not all bits may be allocated. */ 45 #define nr_cpumask_bits nr_cpu_ids 46 #else 47 #define nr_cpumask_bits ((unsigned int)NR_CPUS) 48 #endif 49 50 /* 51 * The following particular system cpumasks and operations manage 52 * possible, present, active and online cpus. 53 * 54 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable 55 * cpu_present_mask - has bit 'cpu' set iff cpu is populated 56 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler 57 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration 58 * 59 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online. 60 * 61 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's 62 * that it is possible might ever be plugged in at anytime during the 63 * life of that system boot. The cpu_present_mask is dynamic(*), 64 * representing which CPUs are currently plugged in. And 65 * cpu_online_mask is the dynamic subset of cpu_present_mask, 66 * indicating those CPUs available for scheduling. 67 * 68 * If HOTPLUG is enabled, then cpu_possible_mask is forced to have 69 * all NR_CPUS bits set, otherwise it is just the set of CPUs that 70 * ACPI reports present at boot. 71 * 72 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically, 73 * depending on what ACPI reports as currently plugged in, otherwise 74 * cpu_present_mask is just a copy of cpu_possible_mask. 75 * 76 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not 77 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot. 78 * 79 * Subtleties: 80 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode 81 * assumption that their single CPU is online. The UP 82 * cpu_{online,possible,present}_masks are placebos. Changing them 83 * will have no useful affect on the following num_*_cpus() 84 * and cpu_*() macros in the UP case. This ugliness is a UP 85 * optimization - don't waste any instructions or memory references 86 * asking if you're online or how many CPUs there are if there is 87 * only one CPU. 88 */ 89 90 extern struct cpumask __cpu_possible_mask; 91 extern struct cpumask __cpu_online_mask; 92 extern struct cpumask __cpu_present_mask; 93 extern struct cpumask __cpu_active_mask; 94 extern struct cpumask __cpu_dying_mask; 95 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask) 96 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask) 97 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask) 98 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask) 99 #define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask) 100 101 extern atomic_t __num_online_cpus; 102 103 extern cpumask_t cpus_booted_once_mask; 104 105 static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) 106 { 107 #ifdef CONFIG_DEBUG_PER_CPU_MAPS 108 WARN_ON_ONCE(cpu >= bits); 109 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */ 110 } 111 112 /* verify cpu argument to cpumask_* operators */ 113 static inline unsigned int cpumask_check(unsigned int cpu) 114 { 115 cpu_max_bits_warn(cpu, nr_cpumask_bits); 116 return cpu; 117 } 118 119 #if NR_CPUS == 1 120 /* Uniprocessor. Assume all masks are "1". */ 121 static inline unsigned int cpumask_first(const struct cpumask *srcp) 122 { 123 return 0; 124 } 125 126 static inline unsigned int cpumask_last(const struct cpumask *srcp) 127 { 128 return 0; 129 } 130 131 /* Valid inputs for n are -1 and 0. */ 132 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) 133 { 134 return n+1; 135 } 136 137 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 138 { 139 return n+1; 140 } 141 142 static inline unsigned int cpumask_next_and(int n, 143 const struct cpumask *srcp, 144 const struct cpumask *andp) 145 { 146 return n+1; 147 } 148 149 static inline unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, 150 int start, bool wrap) 151 { 152 /* cpu0 unless stop condition, wrap and at cpu0, then nr_cpumask_bits */ 153 return (wrap && n == 0); 154 } 155 156 /* cpu must be a valid cpu, ie 0, so there's no other choice. */ 157 static inline unsigned int cpumask_any_but(const struct cpumask *mask, 158 unsigned int cpu) 159 { 160 return 1; 161 } 162 163 static inline unsigned int cpumask_local_spread(unsigned int i, int node) 164 { 165 return 0; 166 } 167 168 static inline int cpumask_any_and_distribute(const struct cpumask *src1p, 169 const struct cpumask *src2p) { 170 return cpumask_next_and(-1, src1p, src2p); 171 } 172 173 static inline int cpumask_any_distribute(const struct cpumask *srcp) 174 { 175 return cpumask_first(srcp); 176 } 177 178 #define for_each_cpu(cpu, mask) \ 179 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 180 #define for_each_cpu_not(cpu, mask) \ 181 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 182 #define for_each_cpu_wrap(cpu, mask, start) \ 183 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start)) 184 #define for_each_cpu_and(cpu, mask1, mask2) \ 185 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) 186 #else 187 /** 188 * cpumask_first - get the first cpu in a cpumask 189 * @srcp: the cpumask pointer 190 * 191 * Returns >= nr_cpu_ids if no cpus set. 192 */ 193 static inline unsigned int cpumask_first(const struct cpumask *srcp) 194 { 195 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits); 196 } 197 198 /** 199 * cpumask_last - get the last CPU in a cpumask 200 * @srcp: - the cpumask pointer 201 * 202 * Returns >= nr_cpumask_bits if no CPUs set. 203 */ 204 static inline unsigned int cpumask_last(const struct cpumask *srcp) 205 { 206 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits); 207 } 208 209 unsigned int __pure cpumask_next(int n, const struct cpumask *srcp); 210 211 /** 212 * cpumask_next_zero - get the next unset cpu in a cpumask 213 * @n: the cpu prior to the place to search (ie. return will be > @n) 214 * @srcp: the cpumask pointer 215 * 216 * Returns >= nr_cpu_ids if no further cpus unset. 217 */ 218 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 219 { 220 /* -1 is a legal arg here. */ 221 if (n != -1) 222 cpumask_check(n); 223 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 224 } 225 226 int __pure cpumask_next_and(int n, const struct cpumask *, const struct cpumask *); 227 int __pure cpumask_any_but(const struct cpumask *mask, unsigned int cpu); 228 unsigned int cpumask_local_spread(unsigned int i, int node); 229 int cpumask_any_and_distribute(const struct cpumask *src1p, 230 const struct cpumask *src2p); 231 int cpumask_any_distribute(const struct cpumask *srcp); 232 233 /** 234 * for_each_cpu - iterate over every cpu in a mask 235 * @cpu: the (optionally unsigned) integer iterator 236 * @mask: the cpumask pointer 237 * 238 * After the loop, cpu is >= nr_cpu_ids. 239 */ 240 #define for_each_cpu(cpu, mask) \ 241 for ((cpu) = -1; \ 242 (cpu) = cpumask_next((cpu), (mask)), \ 243 (cpu) < nr_cpu_ids;) 244 245 /** 246 * for_each_cpu_not - iterate over every cpu in a complemented mask 247 * @cpu: the (optionally unsigned) integer iterator 248 * @mask: the cpumask pointer 249 * 250 * After the loop, cpu is >= nr_cpu_ids. 251 */ 252 #define for_each_cpu_not(cpu, mask) \ 253 for ((cpu) = -1; \ 254 (cpu) = cpumask_next_zero((cpu), (mask)), \ 255 (cpu) < nr_cpu_ids;) 256 257 extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); 258 259 /** 260 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location 261 * @cpu: the (optionally unsigned) integer iterator 262 * @mask: the cpumask poiter 263 * @start: the start location 264 * 265 * The implementation does not assume any bit in @mask is set (including @start). 266 * 267 * After the loop, cpu is >= nr_cpu_ids. 268 */ 269 #define for_each_cpu_wrap(cpu, mask, start) \ 270 for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \ 271 (cpu) < nr_cpumask_bits; \ 272 (cpu) = cpumask_next_wrap((cpu), (mask), (start), true)) 273 274 /** 275 * for_each_cpu_and - iterate over every cpu in both masks 276 * @cpu: the (optionally unsigned) integer iterator 277 * @mask1: the first cpumask pointer 278 * @mask2: the second cpumask pointer 279 * 280 * This saves a temporary CPU mask in many places. It is equivalent to: 281 * struct cpumask tmp; 282 * cpumask_and(&tmp, &mask1, &mask2); 283 * for_each_cpu(cpu, &tmp) 284 * ... 285 * 286 * After the loop, cpu is >= nr_cpu_ids. 287 */ 288 #define for_each_cpu_and(cpu, mask1, mask2) \ 289 for ((cpu) = -1; \ 290 (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \ 291 (cpu) < nr_cpu_ids;) 292 #endif /* SMP */ 293 294 #define CPU_BITS_NONE \ 295 { \ 296 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 297 } 298 299 #define CPU_BITS_CPU0 \ 300 { \ 301 [0] = 1UL \ 302 } 303 304 /** 305 * cpumask_set_cpu - set a cpu in a cpumask 306 * @cpu: cpu number (< nr_cpu_ids) 307 * @dstp: the cpumask pointer 308 */ 309 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 310 { 311 set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 312 } 313 314 static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 315 { 316 __set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 317 } 318 319 320 /** 321 * cpumask_clear_cpu - clear a cpu in a cpumask 322 * @cpu: cpu number (< nr_cpu_ids) 323 * @dstp: the cpumask pointer 324 */ 325 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) 326 { 327 clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 328 } 329 330 static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) 331 { 332 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 333 } 334 335 /** 336 * cpumask_test_cpu - test for a cpu in a cpumask 337 * @cpu: cpu number (< nr_cpu_ids) 338 * @cpumask: the cpumask pointer 339 * 340 * Returns 1 if @cpu is set in @cpumask, else returns 0 341 */ 342 static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) 343 { 344 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); 345 } 346 347 /** 348 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask 349 * @cpu: cpu number (< nr_cpu_ids) 350 * @cpumask: the cpumask pointer 351 * 352 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 353 * 354 * test_and_set_bit wrapper for cpumasks. 355 */ 356 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) 357 { 358 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 359 } 360 361 /** 362 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask 363 * @cpu: cpu number (< nr_cpu_ids) 364 * @cpumask: the cpumask pointer 365 * 366 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 367 * 368 * test_and_clear_bit wrapper for cpumasks. 369 */ 370 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) 371 { 372 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 373 } 374 375 /** 376 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask 377 * @dstp: the cpumask pointer 378 */ 379 static inline void cpumask_setall(struct cpumask *dstp) 380 { 381 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); 382 } 383 384 /** 385 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask 386 * @dstp: the cpumask pointer 387 */ 388 static inline void cpumask_clear(struct cpumask *dstp) 389 { 390 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); 391 } 392 393 /** 394 * cpumask_and - *dstp = *src1p & *src2p 395 * @dstp: the cpumask result 396 * @src1p: the first input 397 * @src2p: the second input 398 * 399 * If *@dstp is empty, returns 0, else returns 1 400 */ 401 static inline int cpumask_and(struct cpumask *dstp, 402 const struct cpumask *src1p, 403 const struct cpumask *src2p) 404 { 405 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), 406 cpumask_bits(src2p), nr_cpumask_bits); 407 } 408 409 /** 410 * cpumask_or - *dstp = *src1p | *src2p 411 * @dstp: the cpumask result 412 * @src1p: the first input 413 * @src2p: the second input 414 */ 415 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, 416 const struct cpumask *src2p) 417 { 418 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), 419 cpumask_bits(src2p), nr_cpumask_bits); 420 } 421 422 /** 423 * cpumask_xor - *dstp = *src1p ^ *src2p 424 * @dstp: the cpumask result 425 * @src1p: the first input 426 * @src2p: the second input 427 */ 428 static inline void cpumask_xor(struct cpumask *dstp, 429 const struct cpumask *src1p, 430 const struct cpumask *src2p) 431 { 432 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), 433 cpumask_bits(src2p), nr_cpumask_bits); 434 } 435 436 /** 437 * cpumask_andnot - *dstp = *src1p & ~*src2p 438 * @dstp: the cpumask result 439 * @src1p: the first input 440 * @src2p: the second input 441 * 442 * If *@dstp is empty, returns 0, else returns 1 443 */ 444 static inline int cpumask_andnot(struct cpumask *dstp, 445 const struct cpumask *src1p, 446 const struct cpumask *src2p) 447 { 448 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), 449 cpumask_bits(src2p), nr_cpumask_bits); 450 } 451 452 /** 453 * cpumask_complement - *dstp = ~*srcp 454 * @dstp: the cpumask result 455 * @srcp: the input to invert 456 */ 457 static inline void cpumask_complement(struct cpumask *dstp, 458 const struct cpumask *srcp) 459 { 460 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), 461 nr_cpumask_bits); 462 } 463 464 /** 465 * cpumask_equal - *src1p == *src2p 466 * @src1p: the first input 467 * @src2p: the second input 468 */ 469 static inline bool cpumask_equal(const struct cpumask *src1p, 470 const struct cpumask *src2p) 471 { 472 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), 473 nr_cpumask_bits); 474 } 475 476 /** 477 * cpumask_or_equal - *src1p | *src2p == *src3p 478 * @src1p: the first input 479 * @src2p: the second input 480 * @src3p: the third input 481 */ 482 static inline bool cpumask_or_equal(const struct cpumask *src1p, 483 const struct cpumask *src2p, 484 const struct cpumask *src3p) 485 { 486 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p), 487 cpumask_bits(src3p), nr_cpumask_bits); 488 } 489 490 /** 491 * cpumask_intersects - (*src1p & *src2p) != 0 492 * @src1p: the first input 493 * @src2p: the second input 494 */ 495 static inline bool cpumask_intersects(const struct cpumask *src1p, 496 const struct cpumask *src2p) 497 { 498 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), 499 nr_cpumask_bits); 500 } 501 502 /** 503 * cpumask_subset - (*src1p & ~*src2p) == 0 504 * @src1p: the first input 505 * @src2p: the second input 506 * 507 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0 508 */ 509 static inline int cpumask_subset(const struct cpumask *src1p, 510 const struct cpumask *src2p) 511 { 512 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p), 513 nr_cpumask_bits); 514 } 515 516 /** 517 * cpumask_empty - *srcp == 0 518 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear. 519 */ 520 static inline bool cpumask_empty(const struct cpumask *srcp) 521 { 522 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits); 523 } 524 525 /** 526 * cpumask_full - *srcp == 0xFFFFFFFF... 527 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set. 528 */ 529 static inline bool cpumask_full(const struct cpumask *srcp) 530 { 531 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits); 532 } 533 534 /** 535 * cpumask_weight - Count of bits in *srcp 536 * @srcp: the cpumask to count bits (< nr_cpu_ids) in. 537 */ 538 static inline unsigned int cpumask_weight(const struct cpumask *srcp) 539 { 540 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits); 541 } 542 543 /** 544 * cpumask_shift_right - *dstp = *srcp >> n 545 * @dstp: the cpumask result 546 * @srcp: the input to shift 547 * @n: the number of bits to shift by 548 */ 549 static inline void cpumask_shift_right(struct cpumask *dstp, 550 const struct cpumask *srcp, int n) 551 { 552 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n, 553 nr_cpumask_bits); 554 } 555 556 /** 557 * cpumask_shift_left - *dstp = *srcp << n 558 * @dstp: the cpumask result 559 * @srcp: the input to shift 560 * @n: the number of bits to shift by 561 */ 562 static inline void cpumask_shift_left(struct cpumask *dstp, 563 const struct cpumask *srcp, int n) 564 { 565 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n, 566 nr_cpumask_bits); 567 } 568 569 /** 570 * cpumask_copy - *dstp = *srcp 571 * @dstp: the result 572 * @srcp: the input cpumask 573 */ 574 static inline void cpumask_copy(struct cpumask *dstp, 575 const struct cpumask *srcp) 576 { 577 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits); 578 } 579 580 /** 581 * cpumask_any - pick a "random" cpu from *srcp 582 * @srcp: the input cpumask 583 * 584 * Returns >= nr_cpu_ids if no cpus set. 585 */ 586 #define cpumask_any(srcp) cpumask_first(srcp) 587 588 /** 589 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2 590 * @src1p: the first input 591 * @src2p: the second input 592 * 593 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and(). 594 */ 595 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p)) 596 597 /** 598 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2 599 * @mask1: the first input cpumask 600 * @mask2: the second input cpumask 601 * 602 * Returns >= nr_cpu_ids if no cpus set. 603 */ 604 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) 605 606 /** 607 * cpumask_of - the cpumask containing just a given cpu 608 * @cpu: the cpu (<= nr_cpu_ids) 609 */ 610 #define cpumask_of(cpu) (get_cpu_mask(cpu)) 611 612 /** 613 * cpumask_parse_user - extract a cpumask from a user string 614 * @buf: the buffer to extract from 615 * @len: the length of the buffer 616 * @dstp: the cpumask to set. 617 * 618 * Returns -errno, or 0 for success. 619 */ 620 static inline int cpumask_parse_user(const char __user *buf, int len, 621 struct cpumask *dstp) 622 { 623 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 624 } 625 626 /** 627 * cpumask_parselist_user - extract a cpumask from a user string 628 * @buf: the buffer to extract from 629 * @len: the length of the buffer 630 * @dstp: the cpumask to set. 631 * 632 * Returns -errno, or 0 for success. 633 */ 634 static inline int cpumask_parselist_user(const char __user *buf, int len, 635 struct cpumask *dstp) 636 { 637 return bitmap_parselist_user(buf, len, cpumask_bits(dstp), 638 nr_cpumask_bits); 639 } 640 641 /** 642 * cpumask_parse - extract a cpumask from a string 643 * @buf: the buffer to extract from 644 * @dstp: the cpumask to set. 645 * 646 * Returns -errno, or 0 for success. 647 */ 648 static inline int cpumask_parse(const char *buf, struct cpumask *dstp) 649 { 650 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits); 651 } 652 653 /** 654 * cpulist_parse - extract a cpumask from a user string of ranges 655 * @buf: the buffer to extract from 656 * @dstp: the cpumask to set. 657 * 658 * Returns -errno, or 0 for success. 659 */ 660 static inline int cpulist_parse(const char *buf, struct cpumask *dstp) 661 { 662 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); 663 } 664 665 /** 666 * cpumask_size - size to allocate for a 'struct cpumask' in bytes 667 */ 668 static inline unsigned int cpumask_size(void) 669 { 670 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long); 671 } 672 673 /* 674 * cpumask_var_t: struct cpumask for stack usage. 675 * 676 * Oh, the wicked games we play! In order to make kernel coding a 677 * little more difficult, we typedef cpumask_var_t to an array or a 678 * pointer: doing &mask on an array is a noop, so it still works. 679 * 680 * ie. 681 * cpumask_var_t tmpmask; 682 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 683 * return -ENOMEM; 684 * 685 * ... use 'tmpmask' like a normal struct cpumask * ... 686 * 687 * free_cpumask_var(tmpmask); 688 * 689 * 690 * However, one notable exception is there. alloc_cpumask_var() allocates 691 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has 692 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. 693 * 694 * cpumask_var_t tmpmask; 695 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 696 * return -ENOMEM; 697 * 698 * var = *tmpmask; 699 * 700 * This code makes NR_CPUS length memcopy and brings to a memory corruption. 701 * cpumask_copy() provide safe copy functionality. 702 * 703 * Note that there is another evil here: If you define a cpumask_var_t 704 * as a percpu variable then the way to obtain the address of the cpumask 705 * structure differently influences what this_cpu_* operation needs to be 706 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use 707 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the 708 * other type of cpumask_var_t implementation is configured. 709 * 710 * Please also note that __cpumask_var_read_mostly can be used to declare 711 * a cpumask_var_t variable itself (not its content) as read mostly. 712 */ 713 #ifdef CONFIG_CPUMASK_OFFSTACK 714 typedef struct cpumask *cpumask_var_t; 715 716 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) 717 #define __cpumask_var_read_mostly __read_mostly 718 719 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 720 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 721 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 722 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 723 void alloc_bootmem_cpumask_var(cpumask_var_t *mask); 724 void free_cpumask_var(cpumask_var_t mask); 725 void free_bootmem_cpumask_var(cpumask_var_t mask); 726 727 static inline bool cpumask_available(cpumask_var_t mask) 728 { 729 return mask != NULL; 730 } 731 732 #else 733 typedef struct cpumask cpumask_var_t[1]; 734 735 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) 736 #define __cpumask_var_read_mostly 737 738 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 739 { 740 return true; 741 } 742 743 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 744 int node) 745 { 746 return true; 747 } 748 749 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 750 { 751 cpumask_clear(*mask); 752 return true; 753 } 754 755 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 756 int node) 757 { 758 cpumask_clear(*mask); 759 return true; 760 } 761 762 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) 763 { 764 } 765 766 static inline void free_cpumask_var(cpumask_var_t mask) 767 { 768 } 769 770 static inline void free_bootmem_cpumask_var(cpumask_var_t mask) 771 { 772 } 773 774 static inline bool cpumask_available(cpumask_var_t mask) 775 { 776 return true; 777 } 778 #endif /* CONFIG_CPUMASK_OFFSTACK */ 779 780 /* It's common to want to use cpu_all_mask in struct member initializers, 781 * so it has to refer to an address rather than a pointer. */ 782 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); 783 #define cpu_all_mask to_cpumask(cpu_all_bits) 784 785 /* First bits of cpu_bit_bitmap are in fact unset. */ 786 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) 787 788 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) 789 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) 790 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) 791 792 /* Wrappers for arch boot code to manipulate normally-constant masks */ 793 void init_cpu_present(const struct cpumask *src); 794 void init_cpu_possible(const struct cpumask *src); 795 void init_cpu_online(const struct cpumask *src); 796 797 static inline void reset_cpu_possible_mask(void) 798 { 799 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS); 800 } 801 802 static inline void 803 set_cpu_possible(unsigned int cpu, bool possible) 804 { 805 if (possible) 806 cpumask_set_cpu(cpu, &__cpu_possible_mask); 807 else 808 cpumask_clear_cpu(cpu, &__cpu_possible_mask); 809 } 810 811 static inline void 812 set_cpu_present(unsigned int cpu, bool present) 813 { 814 if (present) 815 cpumask_set_cpu(cpu, &__cpu_present_mask); 816 else 817 cpumask_clear_cpu(cpu, &__cpu_present_mask); 818 } 819 820 void set_cpu_online(unsigned int cpu, bool online); 821 822 static inline void 823 set_cpu_active(unsigned int cpu, bool active) 824 { 825 if (active) 826 cpumask_set_cpu(cpu, &__cpu_active_mask); 827 else 828 cpumask_clear_cpu(cpu, &__cpu_active_mask); 829 } 830 831 static inline void 832 set_cpu_dying(unsigned int cpu, bool dying) 833 { 834 if (dying) 835 cpumask_set_cpu(cpu, &__cpu_dying_mask); 836 else 837 cpumask_clear_cpu(cpu, &__cpu_dying_mask); 838 } 839 840 /** 841 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * 842 * @bitmap: the bitmap 843 * 844 * There are a few places where cpumask_var_t isn't appropriate and 845 * static cpumasks must be used (eg. very early boot), yet we don't 846 * expose the definition of 'struct cpumask'. 847 * 848 * This does the conversion, and can be used as a constant initializer. 849 */ 850 #define to_cpumask(bitmap) \ 851 ((struct cpumask *)(1 ? (bitmap) \ 852 : (void *)sizeof(__check_is_bitmap(bitmap)))) 853 854 static inline int __check_is_bitmap(const unsigned long *bitmap) 855 { 856 return 1; 857 } 858 859 /* 860 * Special-case data structure for "single bit set only" constant CPU masks. 861 * 862 * We pre-generate all the 64 (or 32) possible bit positions, with enough 863 * padding to the left and the right, and return the constant pointer 864 * appropriately offset. 865 */ 866 extern const unsigned long 867 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; 868 869 static inline const struct cpumask *get_cpu_mask(unsigned int cpu) 870 { 871 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; 872 p -= cpu / BITS_PER_LONG; 873 return to_cpumask(p); 874 } 875 876 #if NR_CPUS > 1 877 /** 878 * num_online_cpus() - Read the number of online CPUs 879 * 880 * Despite the fact that __num_online_cpus is of type atomic_t, this 881 * interface gives only a momentary snapshot and is not protected against 882 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held 883 * region. 884 */ 885 static inline unsigned int num_online_cpus(void) 886 { 887 return atomic_read(&__num_online_cpus); 888 } 889 #define num_possible_cpus() cpumask_weight(cpu_possible_mask) 890 #define num_present_cpus() cpumask_weight(cpu_present_mask) 891 #define num_active_cpus() cpumask_weight(cpu_active_mask) 892 893 static inline bool cpu_online(unsigned int cpu) 894 { 895 return cpumask_test_cpu(cpu, cpu_online_mask); 896 } 897 898 static inline bool cpu_possible(unsigned int cpu) 899 { 900 return cpumask_test_cpu(cpu, cpu_possible_mask); 901 } 902 903 static inline bool cpu_present(unsigned int cpu) 904 { 905 return cpumask_test_cpu(cpu, cpu_present_mask); 906 } 907 908 static inline bool cpu_active(unsigned int cpu) 909 { 910 return cpumask_test_cpu(cpu, cpu_active_mask); 911 } 912 913 static inline bool cpu_dying(unsigned int cpu) 914 { 915 return cpumask_test_cpu(cpu, cpu_dying_mask); 916 } 917 918 #else 919 920 #define num_online_cpus() 1U 921 #define num_possible_cpus() 1U 922 #define num_present_cpus() 1U 923 #define num_active_cpus() 1U 924 925 static inline bool cpu_online(unsigned int cpu) 926 { 927 return cpu == 0; 928 } 929 930 static inline bool cpu_possible(unsigned int cpu) 931 { 932 return cpu == 0; 933 } 934 935 static inline bool cpu_present(unsigned int cpu) 936 { 937 return cpu == 0; 938 } 939 940 static inline bool cpu_active(unsigned int cpu) 941 { 942 return cpu == 0; 943 } 944 945 static inline bool cpu_dying(unsigned int cpu) 946 { 947 return false; 948 } 949 950 #endif /* NR_CPUS > 1 */ 951 952 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) 953 954 #if NR_CPUS <= BITS_PER_LONG 955 #define CPU_BITS_ALL \ 956 { \ 957 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 958 } 959 960 #else /* NR_CPUS > BITS_PER_LONG */ 961 962 #define CPU_BITS_ALL \ 963 { \ 964 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 965 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 966 } 967 #endif /* NR_CPUS > BITS_PER_LONG */ 968 969 /** 970 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either 971 * as comma-separated list of cpus or hex values of cpumask 972 * @list: indicates whether the cpumap must be list 973 * @mask: the cpumask to copy 974 * @buf: the buffer to copy into 975 * 976 * Returns the length of the (null-terminated) @buf string, zero if 977 * nothing is copied. 978 */ 979 static inline ssize_t 980 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) 981 { 982 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), 983 nr_cpu_ids); 984 } 985 986 #if NR_CPUS <= BITS_PER_LONG 987 #define CPU_MASK_ALL \ 988 (cpumask_t) { { \ 989 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 990 } } 991 #else 992 #define CPU_MASK_ALL \ 993 (cpumask_t) { { \ 994 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 995 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 996 } } 997 #endif /* NR_CPUS > BITS_PER_LONG */ 998 999 #define CPU_MASK_NONE \ 1000 (cpumask_t) { { \ 1001 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 1002 } } 1003 1004 #define CPU_MASK_CPU0 \ 1005 (cpumask_t) { { \ 1006 [0] = 1UL \ 1007 } } 1008 1009 #endif /* __LINUX_CPUMASK_H */ 1010